[qusp]

Quote:

Originally Posted by RinksCustoms /img/forum/go_quote.gif ................ The use of polarized electrolytics isn't recommended. I

ummm are you counting film caps in this polarized = bad statement??? usually polarized, because there are many many designs that use a small value film cap as a bypass to a larger value (normally non-polarized) electrolytic cap. are you saying that all these designs are bad designs. this practice is totally common place.

 

[greeny]

Help.
I've lifted the pads off my 5g video.
what should i do?

 

[Seaningtime]

""Both data transferring & music listening through your computer via USB data cable should be safe. Your computer simply will not accept line-out from your iPod via USB cable.

The problems maybe lies in your self-made usb cable equipped with caps, or loose/broken bypass cable from DAC to dock inside your iPod.""

I thought that data listening would not be safe because the signal is unregulated and comes directly from the DAC. Isn't that why the caps are needed in the first place??

But I don't understand why the cable is still working for one ipod, and on the other one it won't, but it was working fine 12 hours ago??

 

[joneeboi]

Quote:

Originally Posted by Seaningtime /img/forum/go_quote.gif <snip>If I plug the diymod with a different cable into the comp it loads up ok?</snip> <snip>Also, if I plug in my diymod through a normal cable to the comp I am able to access it and everything fine...</snip>

I think that's your problem. I couldn't tell you why your DIY cable isn't working, but you might want to investigate that. And how on earth did you fit caps and USB into the same dock? It must be a pretty tight fit depending on how you routed everything.

Quote:

Originally Posted by habba /img/forum/go_quote.gif Help. I've lifted the pads off my 5g video. what should i do?

Which pads did you lift? One of the last resorts is soldering the wire directly to the dock pins hiding behind the hard drive connector on the other side of the board. That's a task in and of itself, but that's what has to happen in these kinds of situations. Check with your DMM if the other solder spots can be used.

 

[Seaningtime]

lol, I got lazy, just cut the wire in a place that is hidden behind my desk, soldered it all back up and taped it. I will use one of those voltmeters later when I get the chance to test all four signal paths

 

[greeny]

The pads on of the green arrows are lifted. i've desolder the capacitors of l2 and l3 and the small ones as well.

 

[Ron.id]

Quote:

Originally Posted by habba /img/forum/go_quote.gif The pads on of the green arrows are lifted. i've desolder the capacitors of l2 and l3 and the small ones as well.

Bad news

As my knowledge, this means your only chance is soldering the wire directly to the dock pins hiding behind the hard drive connector (as joneeboi mentioned earlier).

But it is the most difficult way than other methods. If your soldering tool & skills is not enough, you could easily damage the harddrive connector

... game over.

IMO there's easier way to resolve this, see Ramblingman's diyMOD 5.5G here

 

[qusp]

yeah well its already game over if he doesn't do it.

i'll preface this with the statement that I'm not at all sure what it is you are trying to do with caps in a usb cable;l unless you have made a LOD with caps on 3 and 4 and added a mini usb socket or wired directly to the usb data pins. oh and BTW there is no line signals in the standard usb cable; pins 3 and 4 arent even used in the apple one. audio is passed through the cable as a digital signal, not an analogue one; this bypasses the dac altogether and the audio is processed by the audio card in your computer; if i'm understanding you properly you have inserted caps in the usb signal path?? is that right?? because if you have added caps into the digital I/O that may be your problem. i'm a little bemused by what you are doing with the USB cable unless i'm totally misunderstanding you.

 

[Seaningtime]

Yes, I did add caps in my usb signal path, I put them between the Green and the White wires (Data + and data -)

USB pinout and signals @ pinouts.ru

And when the music plays through the cable it sounds great (It is working again), not just a placebo effect, when I A-B my diymod and ipod classic the difference is very noticable

I don't see what is so wrong with what I did?

Music is taken from the LOD of the iPod which is directly connected to the DAC via the mod. A USB cable is just a cable, wires. What difference does it make if I use a USB cable or a headphone cable to send the signal to my computer or amplifier?
And why do I have to put the caps directly to the usb data pins?
As long as the caps are between the iPod and the next thing in the chain then that is what I set out to do in the first place, no?

And also the line in on my car head unit is USB so I plan on using this cable for that purpose whenever I get a new car to put my sound system into

But I don't mean to be ignorant, I came and asked you guys for help because clearly you guys are the pros. So how should I be making a cable given my circumstances...?

I have 2 sets of caps, I wanted to have one pair used for USB in my car, and one to go to a 1/8th inch headphone jack so that I can use it anywhere like a home system- the other day I ordered a large iPod adapter for this (That has room to fit caps)

 

[joneeboi]

There isn't any indication at all in this thread that one should put capacitors in their USB signal. The closest we ever come to that is back when CAvanessia and I both made docks with USB capability and line out, but there were never caps in the paths of the USB signals then either. It's not just a matter of "caps anywhere in between the iPod and the next thing." The capacitors block DC and respond to AC, so they are put in series with the DAC outputs to protect your equipment. No one has ever said to put capacitors in series with the USB signal in this thread, so I don't know where you got that from. Like qusp said, the Wolfson DAC isn't even used when you hook your iPod to your car stereo's USB input. I have no idea how USB works, but that would be your first clue as to why your dock isn't working like it should. I thought it was just understood that this whole thread was mainly about blocking DC on the audio pins, but I'll be clearer now:

Use capacitors in series with pins 3 and 4, and don't hook anything additional to your USB signal.

 

[Seaningtime]

Ok let me just clarify- After sending the signal from the DAC to the line out of the iPod directly with the mod, there is still another set of outputs specifically for playing through the USB which are totally independent and irrelevant to the mod which was performed?

ie - One can play their iPod through the USB cable and it will have nothing to do with the diymod

 

[joneeboi]

Precisely.

It's not so much that USB should necessarily be considered another audio output, but it just so happens that it can be used that way.

 

[Seaningtime]

Hmm well I feel a little stupid now, lol. But I swear it still sounds good to me... O well, time to do it properly and see the true potential

Thanks guys

 

[Hayduke]

@ Seaning

If you did put caps in the USB signal path, that would explain the description of your problem. You said it "took longer then normal to recognize the iPod". This was likely due to the time it took to charge up the caps. Once they were charged, the signals could pass.

Like others have said though, you should remove them. There is no benefit to be had, and it can only cause problems as you have observed. Luckily, I don't think you could have damaged anything.

I have a question though about your intended application. You said your head unit has a USB input? What do they intend you to connect to it? A laptop or something? Or was the intention to use the standard iPod USB cable? This mod won't help with that application. This will only affect the audio line out on pins 3 and 4 on the dock. If you think the DAC in your head unit is better then the Wolfson DAC inside the iPod, you should just use the standard iPod cable.

If your head unit also has line in plugs on the back, such as RCAs, then you could benefit from this mod. Make yourself a LOD with RCAs instead of a mini phono plug, or use a mini phono-->RCA adapter.

Another option is to build a standard LOD. ie coupling caps inside that terminates with the mini phono. Then build a cable with a female mini phone and male RCAs. The line out on head units are usually on the back, so you could run the cable behind the dash and plug in the RCAs. Then leave the female mini phono somewhere accessible, and you would be able to use the same LOD you will use for your headphone amps

 

[Johannes Freed]

Quick question... Will diyModding the line-out on an iPod Mini affect the headphone out in any way? As in, will it still work?